Fluorinated alkyl compound derivatives have been used as agrochemicals, drugs and intermediates therefor; and processes for preparing various derivatives of the fluorinated alkyl compounds have been known in the art.
In general, the fluorinated alkyl compounds have been prepared by the processes entailing multiple synthetic steps (see: JP 02121961; JP 62190133; JP 8110121; DE 3801248; and, GB 1156912). The processes of the prior art, therefore, have proven to be less than satisfactory in the sense that they do not provide the compounds in a simple and economical manner, because the processes essentially employed reactants hard to handle, and very long, complex and vigorous reaction steps to provide unstable intermediates and the productivities thereofs were relatively low. Accordingly, the processes of prior art have been restricted in light of practical application; in this connection, there have been efforts to develop the fluorinated alkyl compound derivatives in a simple and economical manner.
For instance, K. Tanaka et al discloses a process for preparing fluorinated alkyl compound derivatives substituted with diethylthio group; the process, however, has proven to be less satisfactory in the sense of low yield(52%) since trifluoroacetaldehyde hydrate obtained by reduction of methyl trifluoroacetate with lithium aluminum hydride was employed as a starting material (see: K. Tanaka et al., Chemistry Letters, 175-178(1979)).
S. T. Purrington et al also discloses a process for preparing fluorinated alkyl compound derivatives substituted with diphenylthio group; the process, however, has also proven to be less satisfactory in the sense of low yield (65%) and has not provide various derivatives, since trifluoroacetaldehyde ethylhemiacetal, phosphorus pentaoxide and hexamethyldisiloxane were employed as reactants (See: S. T. Purrington, Journal of Fluorine Chemistry, 43:229-234(1989)).
Accordingly, there is a need in the art for the development of a practical process which can be employed in industrial application.